Oil and gas reservoirs may be exploited by tapping the resources therein via wellbores. Drilling of wellbores may require drilling a considerable distance into the earth. Many oil & gas bearing formations are at sub-sea locations. The direction of drilling may vary from a vertical position to a horizontal position. The wellbore created by drilling may be stabilised by use of casing or lining or by other measures. Tubular bodies (hereinafter “tubulars”) may be positioned in the wellbore. The tubular bodies may be cemented into position. The positioning of tubulars in the wellbore may be complicated by variations in wellbore direction. Tubulars may have mechanical components mounted thereon for the purposes of improving alignment and stable positioning of the tubulars in the wellbore. Correct positioning of the tubulars permits cementing to a satisfactory standard.